1. Field of the Invention
The invention relates to portable readers that enable a link to be set up between a so-called "chip" card or "smart" card and a fixed central processing unit, notably to carry out transactions such as payments, for example.
2. Description of the Prior Art
Chip cards that enable payment transactions to be made directly, in terms of either money or accounting units such as telephone units for example are well known. They comprise a chip fixed into a plastic card having standardized dimensions and provided with a connector which is itself standardized and makes it possible, by means of an electrical connection, to set up the required links with a central processing unit of a reader, said card enabling, for example, the validating of a payment or the setting up of a telephone call.
There also exist known cards that have a number of electronic circuits, including at least one chip, and make it possible, by means of an inductive or radioelectric link, to set up a communication, in order for example to activate the opening of an entry control gate in a place under surveillance as the offices of a firm or to permit payment for services, for example the payment of a toll fee on a highway. These cards generally have the same size as common chip cards but are thicker so as to be capable of housing all the necessary circuits, and they do not have any connector since the link is done without contact.
Finally, there are known cordless telephone sets that are used in cellular radiophone systems and are themselves general-purpose devices. The customizing of these telephone sets, to prevent theft and fraud, is often done by means of a chip card, generally a standard type card, used to send the telephone set the codes needed for its operation and for the identification of the user.
Several trials are currently being made to extend the use of chip cards to a large number of uses, especially in a large number of situations that require the payment of a fee of some kind, such as toll systems, parking, entry into sports centers, etc. In view of the different conditions of use and the particular requirements of the debiting parties, this leads to increasing the number of cards. Thus, a private individual may have to carry at least five cards: a bank card, a phone card, a card to enter the workplace, a highway toll-gate card, and a cellular phone card. If he or she has to visit several establishments for his or her work and use different highway systems, the number of cards to be carried will greatly increase. This will soon become cumbersome and ultimately make people nostalgic about cash.
Various attempts are being made to cope with this increase in the number of specific cards, some of which are known as "electronic wallets". However, the approaches envisaged up to now resolve this problem of proliferation only partially. Above all, there remains the problem of using several different types of links for it would appear to be almost impossible to reduce these different links to only one type, given the different applications that give rise to particular constraints. A single card adapted to all these types of links would in principle be extremely bulky. This, apart form the inconvenience caused, would prevent its use in most of the presently used chip card readers.